Molecular Detection of Colistin Resistance Gene
(MCR-1) in E. coli
Isolated from Cloacal Swabs of Broilers
Muhammad Zulqarnain, Noreen Sarwar*, Aftab Ahmad
Anjum, Sehrish Firyal1, Tahir Yaqub and Masood Rabbani
Institute of Microbiology;1Institute
of Biochemistry and Biotechnology, University of Veterinary and
Animal Sciences, Lahore, Pakistan
*Corresponding author:
noreen.sarwar@uvas.edu.pk
Abstract
The current emergence of
antimicrobial resistance against colistin is a major challenge to treat multi
drug resistant Gram negative bacteria. Broiler chickens can function as a source
for dissemination of antimicrobial resistant strains to humans. In present
study, 150 cloacal swabs of broiler birds, collected from retail shops in
Lahore, were processed for isolation of E.coli. E. coli isolates (n=100) were
tested for antimicrobial sensitivity to colistin sulfate using broth dilution
method. The resistant isolates were tested by polymerase chain reaction for
mcr-1 and mcr-2 genes of colistin resistance. The isolates, found resistant by
broth dilution method, were also checked for pathogenicity by adding congo-red
dye in nutrient agar. Phenotypically colistin resistant isolates were also
tested for other antibiotics e.g. Amoxicilline (30ug), Cefepime (30ug),
Gentamycin (10ug), Chloramphenicol (30mcg), Clindamycin (2ug), Ciprofloxacine
(5ug), Norfloxacin (10ug), Amikacin (30ug), Lincomycin (10ug) and Streptomycin
(10ug) by disc diffusion method. Out of 100 isolates, 59 showed resistance to
colistin while taking MIC as 4mg/L. The colistin resistant E.coli also showed
multidrug resistance against other antibiotics tested. Among 59 phenotypically
colistin resistant isolates, only 7 isolates were possessing mcr-1 gene but none
of the strains was observed bearing mcr-2 gene. About 15% (5/59) colistin
resistant isolates were pathogenic by congo red dye test. The results indicated
presence of mcr-1 harboring E. coli in commercial birds that can contribute in
spread of mcr-1 gene.
To Cite This Article:
Zulqarnain M, Sarwar N, Anjum AA, Firyal S, Yaqub
T and Rabbani M, 2021. Molecular detection of colistin resistance gene (MCR-1)
in E. coli isolated from cloacal swabs
of broilers. Pak Vet J, 41(2): 284-288.
http://dx.doi.org/10.29261/pakvetj/2021.016